This invention relates to food and drink containers and to medical devices utilized for implantation and prosthetic purposes, for the collection, storage and/or administration of physiological solutions. More particularly, this invention relates to food and drink containers and to medical devices for collecting physiological solutions, such as blood, from mammals, particularly humans, the storage of such physiological solutions and the administration of such physiological solutions to mammals. Specifically, this invention relates to food wrapping and containers, drink containers and to medical devices made from vinyl halide polymers containing a migration-resistant polyester resin as a plasticizer for said vinyl halide polymer.
Vinyl halide polymers, particularly polyvinyl chloride, are the resins of choice from which comestibles wrappings and containers and transporting means are made and from which means such as apparatus and devices are made for collecting physiological solutions from humans, storing the solutions and administering the solutions to humans. Similarly, vinyl halide polymers, particularly polyvinyl chloride, are the resins of choice from which medical tubing is prepared and which may be used for transporting fluids such as gases and physiological solutions to or from the human body or which may be implanted in the human body to supplement or replace diseased body tubes such as arteries. Further, vinyl halide resins are used in medical devices which supplement or replace diseased human organs, such as heart valves.
Vinyl halide polymers per se, i.e., unplasticized vinyl halide polymers, are rigid resins which are not amenable to processing procedures such as are used in the formation of films, tubing, formed articles and the like. Accordingly, the vinyl halide resin must be plasticized and phthalates, particularly di-2-ethylhexyl phthalate, have been the plasticizers of choice for vinyl halide polymers regardless of the end use of such polymers. The selection of phthalates as the industry-wide plasticizers of choice for vinyl halide polymers is based on their ready availability, low cost and the processing characteristics they impart to vinyl halide polymers.
A problem which has recently come to the attention of medical authorities, however, is the evidence of the migration of monomeric plasticizers, especially phthalates, such as di-2-ethylhexyl phthalate, from the vinyl halide polymer article, such as food wrapping, tubing, food or blood bag, syringe or the like, to the gas, food or fluid contained in the article. If the vinyl halide resin article is used for the collection of physiological solutions such as mammalian blood for later testing purposes, it is apparent that the migration of the plasticizer from the tubing in which the blood is collected and the bag in which the blood is stored prior to testing, may introduce a discrepancy in the test results. Further, the presence of monomeric phthalate plasticizers in vinyl halide resin articles such as blood bags and blood administration devices has resulted in evidence of migration of the plasticizer to the physiological solution being administered to the mammalian body. Thus, physiological solutions such as blood, glucose and the like may contain monomeric plasticizer which has been leached from the blood bag, syringe, tube, etc. in which it is stored, collected or administered and the plasticizer is then introduced into the body. It, apparently, is not excreted but is stored within the body. Although no evidence has shown that the storage of monomeric phthalate plasticizers within the mammalian body is harmful to health, the possibility that it may be harmful is a subject of major concern.
Accordingly, it is of importance that liquid and solid comestible packagings, wrappings and containers, drink containers and medical tubing, blood bags, syringes and other collection, storage and administration devices for physiological fluids and for organ supplements and implants in mammalian bodies, particularly in humans, be composed of vinyl halide polymers which contain a plasticizer which does not migrate from the medical article or device to the body or to physiological solutions.